Physics-informed energy-balanced modeling and active disturbance rejection control for circulating fluidized bed units

Abstract

Circulating fluidized bed (CFB) units, with many advantages such as low emission and wide fuel adaptability, have been extensively applied to the power and thermal supply. To analyze their dynamic characteristics and design a suitable control strategy, a physics-informed model is derived, which is suitable for the direct energy balance (DEB) structure. By dividing the unit into three modules, a 9th-order nonlinear dynamic model is obtained based on energy conservation and mass conservation principles. The model accuracy is verified by the field running data. The nonlinearity, coupling property and high-order dynamics of the coordinated control system (CCS) are analyzed, and then the advantages of the DEB structure for CFB units are derived theoretically. Finally, the control performance of the DEB structure with proportional–integral–derivative control and active disturbance rejection control (ADRC) is compared based on the field running data. This physics-informed model can offer a solid foundation for a control strategy design under the DEB structure. The advantages of ADRC are validated quantitatively, which shows a promising future in power units.